title: [Glucose-6-phosphate dehydrogenase of Drosophila melanogaster: purification and some properties of normal and mutant enzyme forms].
abstract: Two isozymes of glucose-6-phosphate dehydrogenase (EC 1.1.1.49) (G6PD) of Drosophila melanogaster encoded by allelic genes were purified 3000-fold by biospecific phosphocellulose chromatography, using NADP as the enzyme eluent. Electrophoretically fast isozyme A and slow isozyme B variants prove to contain identical subunits with molecular weight of 54000-55000. G6PD is shown to be a dimer. An antiserum directed to highly purified isozyme A does not inhibit the activity of both isozymes. The mutant forms of G6PD restoring the viability of flies without 6-phosphogluconate dehydrogenase show drastically increased Km values for NADP and/or glucose-6-phosphate. It was demonstrated for two mutations that a sharp (200-fold) magnification of Km value for the substrate followed by a considerable increase in the enzyme thermostability might not exert any essential influence on the Km value for NADP.
mesh_terms: D000483:Alleles; D000818:Animals; D004331:Drosophila melanogaster / Q000201:enzymology* / Q000235:genetics; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D007106:Immune Sera; D007118:Immunoassay; D007527:Isoenzymes / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D046911:Macromolecular Substances; D008970:Molecular Weight; D009154:Mutation
chemical_list: D007106:Immune Sera; D007527:Isoenzymes; D046911:Macromolecular Substances; D005954:Glucosephosphate Dehydrogenase
vernacular_title: Gliukozo-6-fosfatdegidrogenaza Drosophila melanogaster: ochistka i nekotorye svoĭstva fermenta v norme i pri mutatsiiakh.